Control channel resource configuration method, base station, and terminal device

ABSTRACT

Embodiments of this application provide a control channel configuration method, a base station, and a terminal device. The method includes: determining, by a base station, a configuration of a time-frequency resource unit from at least two configurations of a time-frequency resource unit of a control channel; and sending, by the base station, indication information to a terminal device, where the indication information is used to indicate the configuration of the time-frequency resource unit, and the at least two configurations of a time-frequency resource unit include a first configuration and a second configuration. In the embodiments of this application, the base station can flexibly configure the time-frequency resource unit of the control channel. In addition, flexibly configuring a time-frequency resource unit can reduce a probability that time-frequency resource units of different structures are blocked, thereby reducing complexity of detecting the control channel by the terminal device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/749,215, filed on Jan. 22, 2020, now U.S. Pat. No. 11,109,371, whichis a continuation of U.S. patent application Ser. No. 16/236,589, filedon Dec. 30, 2018, now U.S. Pat. No. 10,555,296, which is a continuationof International Application No. PCT/CN2017/108851, filed on Nov. 1,2017, which claims priority to Chinese Patent Application No.201610974288.1, filed on Nov. 3, 2016. All of the afore-mentioned patentapplications are hereby incorporated by reference in their entireties.

TECHNICAL FIELD

This application relates to the communications field, and in particular,to a control channel resource configuration method, a base station, anda terminal device.

BACKGROUND

In a fifth-generation wireless access system standard new radio (NR), abasic unit in frequency domain is a subcarrier, and a basic unit in timedomain is an orthogonal frequency division multiplexing (OFDM) symbol. Aresource element (RE) is a minimum physical resource, and includes onesubcarrier in one OFDM symbol.

In the NR, a basic scheduling unit in time domain is a timeslot(timeslot) or mini-slot, and the slot or mini-slot includes several OFDMsymbols. As shown in FIG. 1, the slot may be divided into a control areaand a data area, and a downlink control channel (PDCCH) carries downlinkcontrol information (DCI) and is transmitted in the control area. Aresource element group (REG) is a time-frequency resource unit thatconstitutes a time-frequency resource for the downlink control channelin the control area.

In an existing solution, the downlink control channel is transmitted byusing a REG of a fixed structure, and configuration is inflexible.

SUMMARY

Embodiments of this application provide a control channel resourceconfiguration method, a base station, and a terminal device, so as toflexibly configure a time-frequency resource unit of a control channelin a control area.

According to a first aspect, a control channel resource configurationmethod is provided, including:

determining, by a base station, a configuration of a time-frequencyresource unit from at least two configurations of a time-frequencyresource unit of a control channel; and

sending, by the base station, indication information to the terminaldevice, where the indication information is used to indicate theconfiguration of the time-frequency resource unit, where the at leasttwo configurations of a time-frequency resource unit include a firstconfiguration and a second configuration;

a time-frequency resource unit of the first configuration occupies oneorthogonal frequency division multiplexing symbol in time domain, and areference signal is located on the orthogonal frequency divisionmultiplexing symbol occupied by the time-frequency resource unit of thefirst configuration; and a time-frequency resource unit of the secondconfiguration occupies at least two orthogonal frequency divisionmultiplexing symbols in time domain, and a reference signal is locatedon at least one of the at least two orthogonal frequency divisionmultiplexing symbols occupied by the time-frequency resource unit of thesecond configuration.

In this embodiment of this application, the base station can flexiblyconfigure the time-frequency resource unit of the control channel in acontrol area.

In addition, flexibly configuring a time-frequency resource unit canreduce a probability that time-frequency resource units of differentstructures are blocked, thereby reducing complexity of detecting thecontrol channel by the terminal device.

In a possible implementation, the control channel is transmitted in atleast one time-frequency resource area in a control area; and thedetermining, by a base station, a configuration of a time-frequencyresource unit from at least two configurations of a time-frequencyresource unit of a control channel includes:

determining, by the base station, a configuration of a time-frequencyresource unit in each of the at least one time-frequency resource areafrom the at least two configurations of a time-frequency resource unit,where the indication information is used to indicate a configuration ofa time domain resource unit in each of the at least one time-frequencyresource area.

In a possible implementation, the control area in which thetime-frequency resource unit of the control channel is located occupiesat least three orthogonal frequency division multiplexing symbols intime domain, and the configuration of the time-frequency resource unitincludes the first configuration and/or the second configuration.

In a possible implementation, the time-frequency resource unit of thesecond configuration is located on at least two adjacent orthogonalfrequency division multiplexing symbols in the orthogonal frequencydivision multiplexing symbols occupied by the control area.

In a possible implementation, in a same time-frequency resource area,the time-frequency resource unit of the first configuration and thetime-frequency resource unit of the second configuration are located ondifferent orthogonal frequency division multiplexing symbols of thecontrol area.

In a possible implementation, each of at least two of the orthogonalfrequency division multiplexing symbols occupied by the time-frequencyresource unit of the second configuration carries a different quantityof reference signals; or each of the orthogonal frequency divisionmultiplexing symbols occupied by the time-frequency resource unit of thesecond configuration carries a same quantity of reference signals.

In a possible implementation, the reference signals respectively carriedin the orthogonal frequency division multiplexing symbols occupied bythe time-frequency resource unit of the second configuration are locatedin a same frequency domain location.

In a possible implementation, the reference signals respectively carriedin the orthogonal frequency division multiplexing symbols occupied bythe time-frequency resource unit of the second configuration are locatedin different frequency domain locations.

In a possible implementation, there is a correspondence between theconfiguration of the time-frequency resource unit and a downlink controlinformation format, and the configuration of the time-frequency resourceunit is indicated by using the downlink control information format; andthe sending, by the base station, indication information to the terminaldevice includes: determining, by the base station based on theconfiguration of the time-frequency resource unit and thecorrespondence, the downlink control information format corresponding tothe configuration of the time-frequency resource unit; and sending, bythe base station, downlink control information in the correspondingformat to the terminal device.

In a possible implementation, the indication information is carried inan indication channel, and the indication channel is transmitted in atime-frequency resource area in the control area.

In a possible implementation, the indication information carried in theindication channel transmitted in the time-frequency resource area isused to indicate a configuration of a time-frequency resource unit inthe time-frequency resource area.

In a possible implementation, the indication information is carried indownlink control information; and the control area includes a basic setarea and an extended set area, a control channel in which the downlinkcontrol information is located is transmitted in the basic set area, andthe configuration of the time-frequency resource unit is a configurationof a time-frequency resource unit of a control channel transmitted inthe extended set area.

In a possible implementation, the control area includes a basic setarea; and a configuration of a time-frequency resource unit of a controlchannel transmitted in the basic set area is pre-configured, or aconfiguration of a time-frequency resource unit of a control channeltransmitted in the basic set area is indicated by using a broadcastchannel.

In a possible implementation, the indication information is carried inhigher layer signaling or system information.

In a possible implementation, the control area in which thetime-frequency resource unit of the control channel is located occupiesat least two orthogonal frequency division multiplexing symbols in timedomain.

According to a second aspect, a control channel resource configurationmethod is provided, including:

receiving, by a terminal device, indication information sent by a basestation, where the indication information is used to indicate aconfiguration of a time-frequency resource unit of a control channel,and the configuration of the time-frequency resource unit is determinedby the base station from at least two configurations of a time-frequencyresource unit; and detecting, by the terminal device, the controlchannel based on the configuration of the time-frequency resource unit,where the at least two configurations of a time-frequency resource unitinclude a first configuration and a second configuration;

a time-frequency resource unit of the first configuration occupies oneorthogonal frequency division multiplexing symbol in time domain, and areference signal is located on the orthogonal frequency divisionmultiplexing symbol occupied by the time-frequency resource unit of thefirst configuration; and a time-frequency resource unit of the secondconfiguration occupies at least two orthogonal frequency divisionmultiplexing symbols in time domain, and a reference signal is locatedon at least one of the at least two orthogonal frequency divisionmultiplexing symbols occupied by the time-frequency resource unit of thesecond configuration.

In this embodiment of this application, the base station can flexiblyconfigure a time-frequency resource unit that constitutes atime-frequency resource for the control channel in a control area.

In addition, flexibly configuring a time-frequency resource unit canreduce a probability that time-frequency resource units of differentstructures are blocked, thereby reducing complexity of detecting thecontrol channel by the terminal device.

In addition, the terminal device detects the control channel based onthe configuration of the time-frequency resource unit indicated by thebase station. This can reduce the complexity of detecting the controlchannel by the terminal device.

In a possible implementation, the control channel is transmitted in atleast one time-frequency resource area in a control area; and theindication information is used to indicate a configuration of a timedomain resource unit in each of the at least one time-frequency resourcearea.

In a possible implementation, the control area occupies at least threeorthogonal frequency division multiplexing symbols in time domain, andthe configuration of the time-frequency resource unit includes the firstconfiguration and/or the second configuration.

In a possible implementation, the time-frequency resource unit of thesecond configuration is located on at least two adjacent orthogonalfrequency division multiplexing symbols in the orthogonal frequencydivision multiplexing symbols occupied by the control area.

In a possible implementation, in a same time-frequency resource area,the time-frequency resource unit of the first configuration and thetime-frequency resource unit of the second configuration are located ondifferent orthogonal frequency division multiplexing symbols of thecontrol area.

In a possible implementation, each of at least two of the orthogonalfrequency division multiplexing symbols occupied by the time-frequencyresource unit of the second configuration carries a different quantityof reference signals; or each of the orthogonal frequency divisionmultiplexing symbols occupied by the time-frequency resource unit of thesecond configuration carries a same quantity of reference signals.

In a possible implementation, the reference signals respectively carriedin the orthogonal frequency division multiplexing symbols occupied bythe time-frequency resource unit of the second configuration are locatedin a same frequency domain location.

In a possible implementation, the reference signals respectively carriedin the orthogonal frequency division multiplexing symbols occupied bythe time-frequency resource unit of the second configuration are locatedin different frequency domain locations.

In a possible implementation, there is a correspondence between theconfiguration of the time-frequency resource unit and a downlink controlinformation format, and the configuration of the time-frequency resourceunit is indicated by using the downlink control information format; andthe receiving, by a terminal device, indication information sent by abase station includes:

receiving, by the terminal device, downlink control information that issent by the base station and that is in the format corresponding to theconfiguration of the time-frequency resource unit.

In a possible implementation, the indication information is carried inan indication channel, and the indication channel is transmitted in atime-frequency resource area in the control area.

In a possible implementation, the indication information carried in theindication channel transmitted in the time-frequency resource area isused to indicate a configuration of a time-frequency resource unit inthe time-frequency resource area.

In a possible implementation, the indication information is carried indownlink control information; and the control area includes a basic setarea and an extended set area, a control channel in which the downlinkcontrol information is located is transmitted in the basic set area, andthe configuration of the time-frequency resource unit is a configurationof a time-frequency resource unit of a control channel transmitted inthe extended set area.

In a possible implementation, the control area includes a basic setarea; and a configuration of a time-frequency resource unit of a controlchannel transmitted in the basic set area is pre-configured, or aconfiguration of a time-frequency resource unit of a control channeltransmitted in the basic set area is indicated by using a broadcastchannel.

In a possible implementation, the indication information is carried inhigher layer signaling or system information.

In a possible implementation, the control area in which thetime-frequency resource unit of the control channel is located occupiesat least two orthogonal frequency division multiplexing symbols in timedomain.

According to a third aspect, a base station is provided, and the basestation is configured to implement the method in any one of the firstaspect or the possible implementations of the first aspect.

Specifically, the base station may include units configured to executethe method in any one of the first aspect or the possibleimplementations of the first aspect.

According to a fourth aspect, a terminal device is provided, and theterminal device is configured to implement the method in any one of thefirst aspect or the possible implementations of the first aspect.

Specifically, the terminal device may include units configured toexecute the method in any one of the first aspect or the possibleimplementations of the first aspect.

According to a fifth aspect, a base station is provided, including aprocessor, a transmitter, a memory, and a bus system, where theprocessor, the transmitter, and the memory are connected to each otherby using the bus system, the memory is configured to store aninstruction or code, and the processor is configured to execute theinstruction or code stored in the memory, so that the base stationexecutes the method in any one of the first aspect or the possibleimplementations of the first aspect.

According to a sixth aspect, a terminal device is provided, including aprocessor, a receiver, a memory, and a bus system, where the processor,the receiver, and the memory are connected to each other by using thebus system, the memory is configured to store an instruction or code,and the processor is configured to execute the instruction or codestored in the memory, so that the terminal device executes the method inany one of the second aspect or the possible implementations of thesecond aspect.

According to a seventh aspect, a computer readable storage medium isprovided, where the computer readable storage medium stores a program,and the program enables a base station to execute the method in any oneof the first aspect or the possible implementations of the first aspect.

According to an eighth aspect, a computer readable storage medium isprovided, where the computer readable storage medium stores a program,and the program enables a terminal device to execute the method in anyone of the second aspect or the possible implementations of the secondaspect.

According to a ninth aspect, an apparatus is provided, including aprocessor and a memory, where the memory stores a computer instruction,and the processor executes the computer instruction stored in thememory, so that the apparatus implements the method in any one of thefirst aspect or the possible implementations of the first aspect, or anyone of the second aspect or the possible implementations of the secondaspect.

According to a tenth aspect, a computer program is provided, where whenthe computer program runs on a computer, the computer executes themethod in any one of the first aspect or the possible implementations ofthe first aspect, or any one of the second aspect or the possibleimplementations of the second aspect.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic structural diagram of a timeslot;

FIG. 2 is a schematic flowchart of a control channel resourceconfiguration method according to an embodiment of this application;

FIG. 3 is a schematic structural diagram of a time-frequency resourceunit of a first configuration according to an embodiment of thisapplication;

FIG. 4 is a schematic structural diagram of a time-frequency resourceunit of a second configuration according to an embodiment of thisapplication;

FIG. 5 is another schematic structural diagram of a time-frequencyresource unit of a second configuration according to an embodiment ofthis application;

FIG. 6 is a schematic diagram of a time-frequency resource areaaccording to an embodiment of this application;

FIG. 7 is a schematic diagram of a configuration of a time-frequencyresource unit according to an embodiment of this application;

FIG. 8 is a schematic diagram of a configuration of a time-frequencyresource unit according to another embodiment of this application;

FIG. 9 is a schematic diagram of a control area;

FIG. 10 is a schematic structural diagram of a base station according toan embodiment of this application;

FIG. 11 is a schematic structural diagram of a base station according toanother embodiment of this application;

FIG. 12 is a schematic structural diagram of a terminal device accordingto an embodiment of this application; and

FIG. 13 is a schematic structural diagram of a terminal device accordingto another embodiment of this application.

DESCRIPTION OF EMBODIMENTS

The following describes the technical solutions in the embodiments ofthis application with reference to the accompanying drawings in theembodiments of this application.

It should be understood that the technical solutions in the embodimentsof this application may be applied to various communications systems,such as Wireless Fidelity (WiFi), Worldwide Interoperability forMicrowave Access (WiMAX), a Global System for Mobile Communications(GSM) system, a Code Division Multiple Access (CDMA) system, a WidebandCode Division Multiple Access (WCDMA) system, a general packet radioservice (GPRS) system, a Long Term Evolution (LTE) system, a Long TermEvolution Advanced (LTE-A) system, a Universal Mobile TelecommunicationsSystem (UMTS), and a cellular system related to the 3rd GenerationPartnership Project (3GPP). The embodiments of this application imposeno limitation. However, for ease of description, the embodiments of thisapplication use an LTE network as an example for description.

The embodiments of this application may be used in wireless networkswith different standards. A radio access network may include differentnetwork elements in different systems. For example, network elements ofthe radio access network include an evolved NodeB (eNodeB or eNB) in theLong Term Evolution (LTE) and the LTE-A, and network elements of theradio access network include a radio network controller (RNC) and aNodeB in the Wideband Code Division Multiple Access (WCDMA). Similarly,other wireless networks such as the Worldwide Interoperability forMicrowave Access (WiMAX) may also use solutions similar to those of theembodiments of this application, but related modules in a base stationsystem may be different. The embodiments of this application impose nolimitation. However, for ease of description, the following embodimentsuse a base station as an example for description.

It should be further understood that in the embodiments of thisapplication, a terminal device may also be referred to as user equipment(UE), a mobile station (MS), a mobile terminal, or the like. Theterminal may communicate with one or more core networks by using a radioaccess network (RAN). For example, the terminal may be a mobile phone(or referred to as a “cellular” phone), or a computer having acommunication function. For example, the terminal may be a portable,pocket-sized, handheld, computer built-in, or in-vehicle mobileapparatus.

It should be understood that, the term “and/or” in the embodiments ofthis application describes only an association relationship fordescribing associated objects and represents that three relationshipsmay exist. For example, A and/or B may represent the following threecases: Only A exists, both A and B exist, and only B exists. Inaddition, the character “/” in this specification generally indicates an“or” relationship between the associated objects.

“First” and “second” in the embodiments of this application are merelyused for distinguishing, and do not represent a meaning of a sequence ora size.

FIG. 2 is a schematic flowchart of a control channel resourceconfiguration method 200 according to an embodiment of this application.As shown in FIG. 2, the method 200 includes the following content.

210. A base station determines a configuration of a time-frequencyresource unit from at least two configurations of a time-frequencyresource unit of a control channel.

The at least two configurations of a time-frequency resource unitinclude a first configuration and a second configuration, and theconfiguration of the time-frequency resource unit is one or more of theat least two configurations of a time-frequency resource unit.

Optionally, a control area in which the time-frequency resource unit ofthe control channel is located occupies at least two orthogonalfrequency division multiplexing symbols in time domain.

The control channel may be a downlink control channel. For example, thecontrol channel may be a PDCCH. For ease of description, the PDCCH isused as an example in the accompanying drawings to describe the controlchannel. However, this embodiment of this application imposes nolimitation thereto. The control channel may alternatively be anotherdownlink control channel.

A time-frequency resource of the control channel may include a pluralityof time-frequency resource units.

The time-frequency resource unit may include at least one RE. Forexample, the time-frequency resource unit may be referred to as a REG

220. The base station sends indication information to a terminal device,where the indication information is used to indicate the configurationof the time-frequency resource unit.

230. After receiving the indication information sent by the basestation, the terminal device detects the control channel based on theconfiguration of the time-frequency resource unit indicated by theindication information.

The configuration of the time-frequency resource unit includes the firstconfiguration or the second configuration.

In this embodiment of this application, the base station can flexiblyconfigure the time-frequency resource unit of the control channel in thecontrol area.

In addition, flexibly configuring a time-frequency resource unit canreduce a probability that time-frequency resource units of differentstructures are blocked, thereby reducing complexity of detecting thecontrol channel by the terminal device.

In addition, the terminal device detects the control channel based onthe configuration of the time-frequency resource unit indicated by thebase station. This can reduce the complexity of detecting the controlchannel by the terminal device.

A time-frequency resource unit of the first configuration occupies oneorthogonal frequency division multiplexing symbol in time domain, and areference signal (RS) is located on the orthogonal frequency divisionmultiplexing symbol occupied by the time-frequency resource unit of thefirst configuration. Using the time-frequency resource unit of the firstconfiguration can reduce a delay, and therefore the time-frequencyresource unit of the first configuration is applicable to a servicehaving a low-delay requirement. As shown in FIG. 3, the time-frequencyresource unit of the first configuration may transmit at least onereference signal.

A time-frequency resource unit of the second configuration occupies atleast two orthogonal frequency division multiplexing symbols in timedomain, and a reference signal is located on at least one of the atleast two orthogonal frequency division multiplexing symbols occupied bythe time-frequency resource unit of the second configuration.

Optionally, the time-frequency resource unit of the second configurationmay further include at least one of the following two implementations.

Implementation 1

Each of at least two of the orthogonal frequency division multiplexingsymbols occupied by the time-frequency resource unit of the secondconfiguration carries a different quantity of reference signals.Optionally, as shown in FIG. 4, the reference signal is located oneither of two orthogonal frequency division multiplexing symbolsoccupied by the time-frequency resource unit of the secondconfiguration. Using the time-frequency resource unit of the secondconfiguration can reduce reference signal overheads, and therefore thetime-frequency resource unit of the second configuration is applicableto a PDCCH in which relatively more information bits need to betransmitted.

Implementation 2

Each of the at least two orthogonal frequency division multiplexingsymbols occupied by the time-frequency resource unit of the secondconfiguration carries a same quantity of reference signals. Optionally,as shown in FIG. 5, the reference signals respectively carried in the atleast two orthogonal frequency division multiplexing symbols occupied bythe time-frequency resource unit of the second configuration are locatedin a same frequency domain location. In other words, a subcarrier onwhich a reference signal carried in a first orthogonal frequencydivision multiplexing symbol in the at least two orthogonal frequencydivision multiplexing symbols occupied by the time-frequency resourceunit of the second configuration is located is the same as a subcarrieron which a reference signal carried in a second orthogonal frequencydivision multiplexing symbol is located. It should be noted that thereference signals respectively carried in the two orthogonal frequencydivision multiplexing symbols occupied by the time-frequency resourceunit of the second configuration may alternatively be located indifferent frequency domain locations. This embodiment of thisapplication imposes no limitation thereto. Sending reference signals ontwo adjacent orthogonal frequency division multiplexing symbols in timedomain by using the time-frequency resource unit of the secondconfiguration can improve channel estimation performance. This manner isapplicable to a limited coverage scenario (for example, a cell edgeuser), and can improve control channel demodulation performance.

It should be understood that FIG. 4 and FIG. 5 merely use two orthogonalfrequency division multiplexing symbols in time domain as an example fordescription, but no limitation is imposed in this embodiment of thisapplication.

In this embodiment of this application, the reference signal may be usedto demodulate the control channel.

It should be understood that a frequency domain location of at least onereference signal transmitted by the time-frequency resource unit is notlimited in this embodiment of this application. For example, sequencesymbols of any two reference signals on a same orthogonal frequencydivision multiplexing symbol in the at least one reference signal may beseparated by at least one subcarrier in frequency domain.

Optionally, the indication information may be further used to indicate atime domain location and/or a frequency domain location of a referencesignal carried in the time-frequency resource unit.

Optionally, the determining, by a base station, a configuration of atime-frequency resource unit from at least two configurations of atime-frequency resource unit of a control channel in step 210 includes:

determining, by the base station, the configuration of thetime-frequency resource unit from the at least two configurations of atime-frequency resource unit based on at least one of a quantity oforthogonal frequency division multiplexing symbols occupied by thecontrol area, a service requirement, or a network environment of theterminal device.

For example, when a service requires a relatively low delay, the basestation may determine to use the time-frequency resource unit of thefirst configuration, so as to meet a low-delay requirement of theservice. When relatively few time-frequency resources exist in thecontrol area, the base station may determine to use the time-frequencyresource unit in Implementation 1, so as to reduce the reference signaloverheads, thereby avoiding a limitation on a capacity of the controlchannel. When the terminal device is located on a cell edge, the basestation may determine to use the time-frequency resource unit inImplementation 2, so as to increase reference signal coverage, therebyimproving the channel estimation performance.

It should be noted that, if the control area occupies one orthogonalfrequency division multiplexing symbol in time domain, the base stationmay determine that the configuration of the time-frequency resource unitis the first configuration.

Therefore, the control channel resource configuration method in thisembodiment of this application can meet requirements in differentscenarios.

The control area may include at least one time-frequency resource area.As shown in FIG. 6, the control area includes three time-frequencyresource areas. One time-frequency resource area may occupy one or moreorthogonal frequency division multiplexing symbols in time domain. Itshould be noted that one time-frequency resource area is located on anorthogonal frequency division multiplexing symbol occupied by thecontrol area in time domain. For example, if the control area occupiestwo orthogonal frequency division multiplexing symbols in time domain,one time-frequency resource area is located on the two orthogonalfrequency division multiplexing symbols occupied by the control area intime domain; or if the control area occupies three orthogonal frequencydivision multiplexing symbols in time domain, one time-frequencyresource area is located on the three orthogonal frequency divisionmultiplexing symbols occupied by the control area in time domain. Thetime-frequency resource area may be referred to as a control subband(control subband). However, this embodiment of this application imposesno limitation thereto.

Optionally, the control channel is transmitted in at least onetime-frequency resource area in the control area. As shown in FIG. 6, aPDCCH 1 is transmitted in a time-frequency resource area 1, and a PDCCH2 is transmitted in a time-frequency resource area 2 and atime-frequency resource area 3. One time-frequency resource area mayinclude at least one time-frequency resource unit. It should beunderstood that, in some embodiments, one time-frequency resource areamay further include a time-frequency resource of another granularity, inaddition to at least one time-frequency resource unit.

In some embodiments, configurations of time-frequency resource units indifferent time-frequency resource areas in the at least onetime-frequency resource area are the same.

In some embodiments, configurations of time-frequency resource units indifferent time-frequency resource areas in the at least onetime-frequency resource area are different. Correspondingly, thedetermining, by a base station, a configuration of a time-frequencyresource unit from at least two configurations of a time-frequencyresource unit of a control channel in step 210 includes: determining, bythe base station, a configuration of a time-frequency resource unit ineach of the at least one time-frequency resource area from the at leasttwo configurations of a time-frequency resource unit. The indicationinformation sent by the base station is used to indicate a configurationof a time domain resource unit in each of the at least onetime-frequency resource area. In other words, when the configurations ofthe time-frequency resource units in the different time-frequencyresource areas in the at least one time-frequency resource area used fortransmitting the control channel in the control area are different, thebase station may indicate the configuration of the time-frequencyresource unit in each time-frequency resource area to the terminaldevice.

In some embodiments, the control area occupies at least two orthogonalfrequency division multiplexing symbols in time domain. Correspondingly,a configuration of a time-frequency resource unit in a firsttime-frequency resource area includes the first configuration, and aconfiguration of a time-frequency resource unit in a secondtime-frequency resource area includes the second configuration. In someembodiments, the control area occupies at least three orthogonalfrequency division multiplexing symbols in time domain, a configurationof a time-frequency resource unit in a first time-frequency resourcearea includes the first configuration, a configuration of atime-frequency resource unit in a second time-frequency resource areaincludes the first configuration and the second configuration, and aconfiguration of a time-frequency resource unit in a thirdtime-frequency resource area includes the second configuration.

When the control area occupies at least two orthogonal frequencydivision multiplexing symbols in time domain, the time-frequencyresource unit of the control channel may include the time-frequencyresource unit of the first configuration (as shown in A in FIG. 7), ormay include the time-frequency resource unit of the second configuration(as shown in B and C in FIG. 7). In FIG. 7, B is the time-frequencyresource unit in Implementation 1, and C is the time-frequency resourceunit in Implementation 2. It should be noted that, as shown in D in FIG.7, if the time-frequency resource of the control channel includes atleast two time-frequency resource units, at least one time-frequencyresource unit may be the time-frequency resource unit in Implementation1, and at least one time-frequency resource unit may be thetime-frequency resource unit in Implementation 2.

It should be noted that, when the control area includes only thetime-frequency resource unit of the first configuration, a plurality oftime-frequency resource units of the first configuration may berespectively located on different orthogonal frequency divisionmultiplexing symbols of the control area, as shown in A in FIG. 7; orthe time-frequency resource unit of the first configuration may merelyoccupy one of the at least two orthogonal frequency divisionmultiplexing symbols of the control area. In addition, when theplurality of time-frequency resource units of the first configurationare respectively located on the at least two orthogonal frequencydivision multiplexing symbols of the control area, frequency domainlocations of the plurality of time-frequency resource units of the firstconfiguration on the at least two orthogonal frequency divisionmultiplexing symbols may be the same or may be different. Thisembodiment of this application imposes no limitation thereto.

Optionally, the control area occupies at least three orthogonalfrequency division multiplexing symbols in time domain, and theconfiguration of the time-frequency resource unit includes the firstconfiguration and/or the second configuration.

Optionally, the time-frequency resource unit of the second configurationis located on at least two adjacent orthogonal frequency divisionmultiplexing symbols in the orthogonal frequency division multiplexingsymbols occupied by the control area.

In some embodiments, the control area occupies at least three orthogonalfrequency division multiplexing symbols in time domain, and thetime-frequency resource unit of the control channel may include only thetime-frequency resource unit of the first configuration (as shown in Ain FIG. 8), or may include only the time-frequency resource unit of thesecond configuration.

In some embodiments, the time-frequency resource unit of the secondconfiguration occupies at least two orthogonal frequency divisionmultiplexing symbols in time domain. Correspondingly, the configurationof the time-frequency resource unit may include the first configurationand the second configuration. To be specific, the time-frequencyresource unit of the control channel may include the time-frequencyresource unit of the first configuration and the time-frequency resourceunit of the second configuration.

The time-frequency resource unit of the second configuration may belocated on at least two adjacent orthogonal frequency divisionmultiplexing symbols (as shown in B and C in FIG. 8). It should beunderstood that the time-frequency resource unit of the secondconfiguration in B and C in FIG. 8 may include the time-frequencyresource unit of the second configuration in Implementation 1, or mayinclude the time-frequency resource unit of the second configuration inImplementation 2, or may include the time-frequency resource unit of thesecond configuration in Implementation 1 and the time-frequency resourceunit of the second configuration in Implementation 2.

It should be noted that, when the time-frequency resource unit of thecontrol channel includes only the time-frequency resource unit of thefirst configuration, a plurality of time-frequency resource units of thefirst configuration may be respectively located on different orthogonalfrequency division multiplexing symbols of the control area, as shown inA in FIG. 8; or the time-frequency resource unit of the firstconfiguration may be merely located on at least some orthogonalfrequency division multiplexing symbols of the control area. Inaddition, when the plurality of time-frequency resource units of thefirst configuration are respectively located on the at least someorthogonal frequency division multiplexing symbols of the control area,frequency domain locations of the plurality of time-frequency resourceunits of the first configuration on the orthogonal frequency divisionmultiplexing symbols may be the same or may be different. Thisembodiment of this application imposes no limitation thereto. It shouldbe further noted that a frequency domain location of the time-frequencyresource unit of the second configuration located on at least twoorthogonal frequency division multiplexing symbols may be the same as ormay be different from that of the time-frequency resource unit of thefirst configuration located on one orthogonal frequency divisionmultiplexing symbol. This embodiment of this application imposes nolimitation thereto. A, B, and C in FIG. 8 are merely examples, and shallnot constitute any limitation on this embodiment of this application.

Optionally, in step 220, the base station may send the indicationinformation in a plurality of implementations. The following uses fourimplementations as an example for description.

First Implementation

There is a correspondence between the configuration of thetime-frequency resource unit and a downlink control information format,and the configuration of the time-frequency resource unit is indicatedby using the downlink control information format. The downlink controlinformation format may be used to indicate a configuration of atime-frequency resource unit of a control channel transmitted after apreset time period (for example, at least one timeslot).

Correspondingly, the sending, by the base station, indicationinformation to a terminal device in step 220 includes:

determining, by the base station based on the configuration of thetime-frequency resource unit and the correspondence, the downlinkcontrol information format corresponding to the configuration of thetime-frequency resource unit; and sending, by the base station, downlinkcontrol information in the corresponding format to the terminal device.

After receiving the downlink control information in the correspondingformat, the terminal device may determine, based on the correspondingformat and the correspondence between the configuration of thetime-frequency resource unit and the downlink control informationformat, the configuration of the time-frequency resource unit of thecontrol channel transmitted after the preset time period.

Second Implementation

An indication channel may be predefined, and the indication channel isused to transmit the indication information used to indicate theconfiguration of the time-frequency resource unit, that is, theindication information may be carried in the indication channel.

Correspondingly, the sending, by the base station, indicationinformation to a terminal device in step 220 includes:

sending, by the base station, the indication information to the terminaldevice by using the indication channel.

The indication information may include information of at least one bit.For example, the indication information may include 1-bit information,2-bit information, or 3-bit information.

Optionally, the indication channel may be transmitted in thetime-frequency resource area in the control area.

In some embodiments, configurations of time-frequency resource units indifferent time-frequency resource areas in the at least onetime-frequency resource area used for transmitting the control channelare different.

Optionally, an indication channel transmitted in each time-frequencyresource area is used to indicate a configuration of a time-frequencyresource unit in the current time-frequency resource area.

Third Implementation

The indication information is carried in downlink control information.

As shown in FIG. 9, the control area may include a basic set area and anextended set area, a control channel in which the downlink controlinformation is located is transmitted in the basic set area, and theconfiguration of the time-frequency resource unit indicated by theindication information is a configuration of a time-frequency resourceunit of a control channel transmitted in the extended set area.

Correspondingly, the sending, by the base station, indicationinformation to a terminal device in step 220 includes:

sending, by the base station, the downlink control information to theterminal device, where the downlink control information includes theindication information, and the control channel in which the downlinkcontrol information is located is transmitted in the basic set area.

Optionally, a configuration of a time-frequency resource unit of acontrol channel transmitted in the basic set area may be preset, or maybe indicated by system information, or may be indicated by using abroadcast channel.

Fourth Implementation

The indication information is carried in higher layer signaling orsystem information.

Correspondingly, the sending, by the base station, indicationinformation to a terminal device in step 220 includes:

sending, by the base station, the higher layer signaling or the systeminformation to the terminal device, where the higher layer signaling orthe system information carries the indication information.

The higher layer signaling may be radio resource control (Radio ResourceControl, RRC) signaling, and the system information may be a masterinformation block (Master Information Block, MIB).

At least one bit may be set in the higher layer signaling or the systeminformation to represent the configuration of the time-frequencyresource unit.

In this embodiment of this application, an information bit of at leastone bit may be used to represent the indication information used toindicate the configuration of the time-frequency resource unit.

For example, when the control area occupies two orthogonal frequencydivision multiplexing symbols in time domain, a 2-bit information bitmay be used to represent the indication information. For example, the2-bit information bit may be set in the higher layer signaling, thesystem information, or the downlink control information, and a meaningof the 2-bit information bit is as follows:

00: The configuration of the time-frequency resource unit includes thefirst configuration.

01: The configuration of the time-frequency resource unit includes thesecond configuration.

10-11: Reserved.

For example, when the control area occupies three orthogonal frequencydivision multiplexing symbols in time domain, a 3-bit information bitmay be used to represent the indication information. For example, the3-bit information bit may be set in the higher layer signaling, thesystem information, or the downlink control information, and a meaningof the 3-bit information bit is as follows:

000: The configuration of the time-frequency resource unit includes thefirst configuration.

001: The configuration of the time-frequency resource unit includes thefirst configuration and the second configuration.

010: The configuration of the time-frequency resource unit includes thesecond configuration.

011-111: Reserved.

It should be understood that the foregoing merely uses two bits andthree bits as an example for description. However, this embodiment ofthis application imposes no limitation thereto. Another quantity of bitsmay also be used to represent the indication information. For example,when one bit is used to represent the indication information, “0” mayindicate that the configuration of the time-frequency resource unitincludes the first configuration, and “1” may indicate that theconfiguration of the time-frequency resource unit includes the secondconfiguration.

It should be understood that, when the second configuration includes aplurality of implementations, the indication information may be furtherused to indicate an implementation used by the second configuration.

Optionally, the indication information may further indicate a timedomain location and/or a frequency domain location of a reference signalcarried in the time-frequency resource unit. Therefore, complexity ofdetecting the reference signal by the terminal device can be reduced.

Optionally, the indication information may further indicate a solutionof transmitting the control channel. The solution of transmitting thecontrol channel may be a transmit diversity solution, a beamformingsolution, or the like. Therefore, the solution of transmitting thecontrol channel by the terminal device can be flexibly scheduled.

With reference to FIG. 2 to FIG. 9, the foregoing describes the controlchannel resource configuration method according to the embodiment ofthis application. With reference to FIG. 10 to FIG. 13, the followingdescribes a base station and a terminal device according to embodimentsof this application.

FIG. 10 is a schematic structural diagram of a base station 1000according to an embodiment of this application. As shown in FIG. 10, thebase station 1000 includes a processing unit 1010 and a sending unit1020.

The processing unit 1010 is configured to determine a configuration of atime-frequency resource unit from at least two configurations of atime-frequency resource unit of a control channel.

The sending unit 1020 is configured to send indication information to aterminal device, where the indication information is used to indicatethe configuration of the time-frequency resource unit determined by theprocessing unit 1010.

The at least two configurations of a time-frequency resource unitinclude a first configuration and a second configuration.

A time-frequency resource unit of the first configuration occupies oneorthogonal frequency division multiplexing symbol in time domain, and areference signal is located on the orthogonal frequency divisionmultiplexing symbol occupied by the time-frequency resource unit of thefirst configuration.

A time-frequency resource unit of the second configuration occupies atleast two orthogonal frequency division multiplexing symbols in timedomain, and a reference signal is located on at least one of the atleast two orthogonal frequency division multiplexing symbols occupied bythe time-frequency resource unit of the second configuration.

In this embodiment of this application, the base station can flexiblyconfigure the time-frequency resource unit of the control channel in acontrol area.

In addition, flexibly configuring a time-frequency resource unit canreduce a probability that time-frequency resource units of differentstructures are blocked, thereby reducing complexity of detecting thecontrol channel by the terminal device.

Optionally, a control area in which the time-frequency resource unit ofthe control channel is located occupies at least two orthogonalfrequency division multiplexing symbols in time domain.

Optionally, the control channel is transmitted in at least onetime-frequency resource area in a control area. Correspondingly, theprocessing unit 1010 may be specifically configured to determine aconfiguration of a time-frequency resource unit in each of the at leastone time-frequency resource area from the at least two configurations ofa time-frequency resource unit. The indication information is used toindicate a configuration of a time domain resource unit in each of theat least one time-frequency resource area.

Optionally, the control area in which the time-frequency resource unitof the control channel is located occupies at least three orthogonalfrequency division multiplexing symbols in time domain, and theconfiguration of the time-frequency resource unit includes the firstconfiguration and/or the second configuration.

Optionally, the time-frequency resource unit of the second configurationis located on at least two adjacent orthogonal frequency divisionmultiplexing symbols in the orthogonal frequency division multiplexingsymbols occupied by the control area.

Optionally, in a same time-frequency resource area, the time-frequencyresource unit of the first configuration and the time-frequency resourceunit of the second configuration are located on different orthogonalfrequency division multiplexing symbols of the control area.

Optionally, each of at least two of the orthogonal frequency divisionmultiplexing symbols occupied by the time-frequency resource unit of thesecond configuration carries a different quantity of reference signals;or each of the orthogonal frequency division multiplexing symbolsoccupied by the time-frequency resource unit of the second configurationcarries a same quantity of reference signals.

Optionally, the reference signals respectively carried in the orthogonalfrequency division multiplexing symbols occupied by the time-frequencyresource unit of the second configuration are located in a samefrequency domain location.

Optionally, there is a correspondence between the configuration of thetime-frequency resource unit and a downlink control information format,and the configuration of the time-frequency resource unit is indicatedby using the downlink control information format. Correspondingly, theprocessing unit 1010 is further configured to determine, based on theconfiguration of the time-frequency resource unit and thecorrespondence, the downlink control information format corresponding tothe configuration of the time-frequency resource unit; and the sendingunit 1020 is specifically configured to send downlink controlinformation in the corresponding format to the terminal device.

Optionally, the indication information is carried in an indicationchannel, and the indication channel is transmitted in a time-frequencyresource area in the control area.

Optionally, the control area includes a basic set area and an extendedset area.

Optionally, the indication information is carried in the downlinkcontrol information, a control channel in which the downlink controlinformation is located is transmitted in the basic set area, and theconfiguration of the time-frequency resource unit is a configuration ofa time-frequency resource unit that constitutes a time-frequencyresource for a control channel transmitted in the extended set area.

Optionally, a configuration of a time-frequency resource unit of acontrol channel transmitted in the basic set area is pre-configured, ora configuration of a time-frequency resource unit of a control channeltransmitted in the basic set area is indicated by using a broadcastchannel.

Optionally, the indication information is carried in higher layersignaling or system information.

It should be understood that the base station 1000 according to thisembodiment of this application may correspond to the base station in thecontrol channel configuration method 200 according to the embodiment ofthis application. In addition, the foregoing and other operations and/orfunctions of the units in the base station 1000 are intended toimplement corresponding procedures of the base station in the method 200in FIG. 2. For brevity, details are not described herein again.

It should be noted that the processing unit 1010 may be implemented by aprocessor, and the sending unit 1020 may be implemented by atransmitter. FIG. 11 is a schematic structural diagram of a base station1100 according to another embodiment of this application. As shown inFIG. 11, the base station 1100 includes a processor 1110, a transmitter1120, a memory 1130, and a bus system 1140. All components of the basestation 1100 are coupled together by using the bus system 1140.

The memory 1130 may be configured to store code or the like executed bythe processor 1110. The transmitter 1120 is configured to send a signalunder control of the processor 1110.

Specifically, the processor 1110 is configured to implement a functionof the processing unit 1010, and the transmitter 1120 is configured toimplement a function of the sending unit 1020.

It should be understood that the base station 1100 according to thisembodiment of this application may correspond to the base station in thecontrol channel configuration method 200 according to the embodiment ofthis application and the base station 1000 according to the embodimentof this application. In addition, the foregoing and other operationsand/or functions of the units in the base station 1100 are intended toimplement corresponding procedures of the base station in the method 200in FIG. 2. For brevity, details are not described herein again.

FIG. 12 is a schematic structural diagram of a terminal device 1200according to an embodiment of this application. As shown in FIG. 12, theterminal device 1200 includes a receiving unit 1210 and a detection unit1220.

The receiving unit 1210 is configured to receive indication informationsent by a base station, where the indication information is used toindicate a configuration of a time-frequency resource unit thatconstitutes a time-frequency resource for a control channel, and theconfiguration of the time-frequency resource unit is determined by thebase station from at least two configurations of a time-frequencyresource unit.

The detection unit 1220 is configured to detect the control channelbased on the configuration of the time-frequency resource unit indicatedby the indication information received by the receiving unit 1210.

The at least two configurations of a time-frequency resource unitinclude a first configuration and a second configuration.

A time-frequency resource unit of the first configuration occupies oneorthogonal frequency division multiplexing symbol in time domain, and areference signal is located on the orthogonal frequency divisionmultiplexing symbol occupied by the time-frequency resource unit of thefirst configuration.

A time-frequency resource unit of the second configuration occupies atleast two orthogonal frequency division multiplexing symbols in timedomain, and a reference signal is located on at least one of the atleast two orthogonal frequency division multiplexing symbols occupied bythe time-frequency resource unit of the second configuration.

In this embodiment of this application, the base station can flexiblyconfigure the time-frequency resource unit of the control channel in acontrol area.

In addition, flexibly configuring a time-frequency resource unit canreduce a probability that time-frequency resource units of differentstructures are blocked, thereby reducing complexity of detecting thecontrol channel by the terminal device.

In addition, the terminal device detects the control channel based onthe configuration of the time-frequency resource unit indicated by thebase station. This can reduce the complexity of detecting the controlchannel by the terminal device.

Optionally, a control area in which the time-frequency resource unit ofthe control channel is located occupies at least two orthogonalfrequency division multiplexing symbols in time domain.

Optionally, the control channel is transmitted in at least onetime-frequency resource area in a control area; and the indicationinformation is used to indicate a configuration of a time domainresource unit in each of the at least one time-frequency resource area.

Optionally, the control area occupies at least three orthogonalfrequency division multiplexing symbols in time domain, and theconfiguration of the time-frequency resource unit includes the firstconfiguration and/or the second configuration.

Optionally, the time-frequency resource unit of the second configurationis located on at least two adjacent orthogonal frequency divisionmultiplexing symbols in the orthogonal frequency division multiplexingsymbols occupied by the control area.

Optionally, in a same time-frequency resource area, the time-frequencyresource unit of the first configuration and the time-frequency resourceunit of the second configuration are located on different orthogonalfrequency division multiplexing symbols of the control area.

Optionally, each of at least two of the orthogonal frequency divisionmultiplexing symbols occupied by the time-frequency resource unit of thesecond configuration carries a different quantity of reference signals;or each of the orthogonal frequency division multiplexing symbolsoccupied by the time-frequency resource unit of the second configurationcarries a same quantity of reference signals.

Optionally, the reference signals respectively carried in the orthogonalfrequency division multiplexing symbols occupied by the time-frequencyresource unit of the second configuration are located in a samefrequency domain location.

Optionally, there is a correspondence between the configuration of thetime-frequency resource unit and a downlink control information format,and the configuration of the time-frequency resource unit is indicatedby using the downlink control information format. Correspondingly, thereceiving unit 1210 is specifically configured to receive downlinkcontrol information that is sent by the base station and that is in theformat corresponding to the configuration of the time-frequency resourceunit.

Optionally, the indication information is carried in an indicationchannel, and the indication channel is transmitted in a time-frequencyresource area in the control area.

Optionally, the indication information carried in the indication channeltransmitted in the time-frequency resource area is used to indicate aconfiguration of a time-frequency resource unit in the time-frequencyresource area.

Optionally, the indication information is carried in downlink controlinformation; and the control area includes a basic set area and anextended set area, a control channel in which the downlink controlinformation is located is transmitted in the basic set area, and theconfiguration of the time-frequency resource unit is a configuration ofa time-frequency resource unit of a control channel transmitted in theextended set area.

Optionally, the control area includes a basic set area; and aconfiguration of a time-frequency resource unit of a control channeltransmitted in the basic set area is pre-configured, or a configurationof a time-frequency resource unit of a control channel transmitted inthe basic set area is indicated by using a broadcast channel.

Optionally, the indication information is carried in higher layersignaling or system information.

It should be understood that the terminal device 1200 according to thisembodiment of this application may correspond to the terminal device inthe control channel configuration method 200 according to the embodimentof this application. In addition, the foregoing and other operationsand/or functions of the units in the terminal device 1200 are intendedto implement corresponding procedures of the terminal device in themethod 200 in FIG. 2. For brevity, details are not described hereinagain.

It should be noted that the receiving unit 1210 may be implemented by areceiver, and the detection unit 1220 may be implemented by a processor.FIG. 13 is a schematic structural diagram of a terminal device 1300according to another embodiment of this application. As shown in FIG.13, the terminal device 1300 includes a processor 1310, a receiver 1320,a memory 1330, and a bus system 1340. All components of the terminaldevice 1300 are coupled together by using the bus system 1340.

The memory 1330 may be configured to store code or the like executed bythe processor 1310. The receiver 1320 is configured to receive a signalunder control of the processor 1310.

Specifically, the processor 1310 is configured to implement a functionof the detection unit 1220, and the receiver 1320 is configured toimplement a function of the receiving unit 1210.

It should be understood that the terminal device 1300 according to thisembodiment of this application may correspond to the terminal device inthe control channel configuration method 200 according to the embodimentof this application and the terminal device 1200 according to theembodiment of this application. In addition, the foregoing and otheroperations and/or functions of the units in the terminal device 1300 areintended to implement corresponding procedures of the terminal device inthe method 200 in FIG. 2. For brevity, details are not described hereinagain.

It should be noted that, in addition to a data bus, the bus system inthe foregoing embodiments may further include a power bus, a controlbus, a status signal bus, and the like. For ease of representation,various buses are marked as the bus system in the figure.

The memory in the foregoing embodiments may include a volatile memory,such as a random access memory (RAM); the memory may include anonvolatile memory, such as a flash memory, a hard disk drive (HDD), ora solid state drive (SSD); or the memory may include a combination ofthe foregoing memories.

In the foregoing embodiments, the processor may be a central processingunit (CPU), a network processor (NP), or a combination of a CPU and anNP. The processor may further include a hardware chip. The hardware chipmay be an application-specific integrated circuit (ASIC), a programmablelogic device (PLD), or a combination thereof. The PLD may be a complexprogrammable logic device (CPLD), a field-programmable gate array(FPGA), generic array logic (GAL), or any combination thereof.

A person of ordinary skill in the art may be aware that, in combinationwith the examples described in the embodiments disclosed in thisspecification, units and algorithm steps may be implemented byelectronic hardware or a combination of computer software and electronichardware. Whether the functions are performed by hardware or softwaredepends on particular applications and design constraint conditions ofthe technical solutions. A person skilled in the art may use differentmethods to implement the described functions for each particularapplication, but it should not be considered that the implementationgoes beyond the scope of the embodiments of this application.

It may be clearly understood by a person skilled in the art that, forthe purpose of convenient and brief description, for a detailed workingprocess of the foregoing system, apparatus, and unit, reference may bemade to a corresponding process in the foregoing method embodiments, anddetails are not described herein again.

In the several embodiments provided in this application, it should beunderstood that the disclosed system, apparatus, and method may beimplemented in other manners. For example, the described apparatusembodiment is merely an example. For example, the unit division ismerely logical function division and may be other division in actualimplementation. For example, a plurality of units or components may becombined or integrated into another system, or some features may beignored or not performed. In addition, the displayed or discussed mutualcouplings or direct couplings or communication connections may beimplemented by using some interfaces. The indirect couplings orcommunication connections between the apparatuses or units may beimplemented in electrical, mechanical, or other forms.

The units described as separate parts may or may not be physicallyseparate, and parts displayed as units may or may not be physical units,may be located in one position, or may be distributed on a plurality ofnetwork units. Some or all of the units may be selected according toactual requirements to achieve the objectives of the solutions of theembodiments.

In addition, functional units in the embodiments of this application maybe integrated into one processing unit, or each of the units may existalone physically, or two or more units are integrated into one unit.

When the functions are implemented in the form of a software functionalunit and sold or used as an independent product, the functions may bestored in a computer-readable storage medium. Based on such anunderstanding, the technical solutions of the embodiments of thisapplication essentially, or the part contributing to the prior art, orsome of the technical solutions may be implemented in a form of asoftware product. The computer software product is stored in a storagemedium, and includes several instructions for instructing a computerdevice (which may be a personal computer, a server, a network device, orthe like) to perform all or some of the steps of the methods describedin the embodiments of this application. The foregoing storage mediumincludes: any medium that can store program code, such as a USB flashdrive, a removable hard disk, a read-only memory (ROM), a random accessmemory (RAM), a magnetic disk, or an optical disc.

The foregoing descriptions are merely specific implementations of thisapplication, but are not intended to limit the protection scope of thisapplication. Any variation or replacement readily figured out by aperson skilled in the art within the technical scope disclosed in thisapplication shall fall within the protection scope of this application.Therefore, the protection scope of this application shall be subject tothe protection scope of the claims.

What is claimed is:
 1. A method, comprising: determining, by a basestation, a configuration of a time-frequency resource unit from at leasttwo configurations of time-frequency resource units of control channels;and sending, by the base station, indication information to a terminaldevice, wherein the indication information indicates the configuration,wherein: the at least two configurations comprise a first configurationand a second configuration, the first configuration is corresponding toa first time-frequency resource unit of a control channel, and thesecond configuration is corresponding to a second time-frequencyresource unit of a control channel, the first time-frequency resourceunit occupies one orthogonal frequency division multiplexing (OFDM)symbol in time domain, and a demodulation reference signal is located inthe one OFDM symbol occupied by the first time-frequency resource unit;and the second time-frequency resource unit occupies at least two OFDMsymbols in time domain, and a demodulation reference signal is locatedin at least one of the at least two OFDM symbols occupied by the secondtime-frequency resource unit.
 2. The method according to claim 1,wherein: the at least two OFDM symbols occupied by the secondtime-frequency resource unit are adjacent OFDM symbols.
 3. The methodaccording to claim 2, wherein: in each second time-frequency resourceunit, each of the OFDM symbols occupied by the second time-frequencyresource unit carries a same quantity of demodulation reference signals.4. The method according to claim 2, wherein: in each secondtime-frequency resource unit of the control channel, the demodulationreference signals carried in each of the OFDM symbols occupied by thesecond time-frequency resource unit are located in a same frequencydomain location.
 5. The method according to claim 1, wherein: thetime-frequency resource of the control channel includes a plurality offirst time-frequency resource units or second time-frequency resourceunits.
 6. The method according to claim 1, wherein: the indicationinformation is carried in higher layer signaling or system information.7. A method, comprising: receiving, by a terminal device, indicationinformation from a base station, wherein the indication informationindicates a configuration of a time-frequency resource unit of a controlchannel, and the configuration is one of at least two configurations oftime-frequency resource unis; detecting, by the terminal device, thecontrol channel based on the configuration, wherein: the at least twoconfigurations comprise a first configuration and a secondconfiguration, the first configuration is corresponding to a firsttime-frequency resource unit of a control channel, and the secondconfiguration is corresponding to a second time-frequency resource unitof a control channel, the first time-frequency resource unit occupiesone orthogonal frequency division multiplexing (OFDM) symbol in timedomain, and a demodulation reference signal is located in the one OFDMsymbol occupied by the first time-frequency resource unit; and thesecond time-frequency resource unit occupies at least two OFDM symbolsin time domain, and a demodulation reference signal is located in atleast one of the at least two OFDM symbols occupied by the secondtime-frequency resource unit.
 8. The method according to claim 7,wherein: the at least two OFDM symbols occupied by the secondtime-frequency resource unit are adjacent OFDM symbols.
 9. The methodaccording to claim 8, wherein: in each second time-frequency resourceunit, each of the OFDM symbols occupied by the second time-frequencyresource unit of the second configuration carries a same quantity ofdemodulation reference signals.
 10. The method according to claim 8,wherein: in each second time-frequency resource unit, the demodulationreference signals carried in each of the OFDM symbols occupied by thesecond time-frequency resource unit are located in a same frequencydomain location.
 11. The method according to claim 7, wherein: thetime-frequency resource of the control channel includes a plurality offirst time-frequency resource units or second time-frequency resourceunits.
 12. The method according to claim 7, wherein: the indicationinformation is carried in higher layer signaling or system information.13. An apparatus, comprising: one or more processors, and anon-transitory storage medium configure to store program instructions;wherein, when executed by the one or more processors, the instructionscause the apparatus to perform a method that comprises: determining aconfiguration of a time-frequency resource unit from at least twoconfigurations of time-frequency resource units of control channels; andsending indication information to a terminal device, wherein theindication information indicates the configuration, wherein: the atleast two configurations comprise a first configuration and a secondconfiguration, the first configuration is corresponding to a firsttime-frequency resource unit of a control channel, and the secondconfiguration is corresponding to a second time-frequency resource unitof a control channel, the first time-frequency resource unit occupiesone orthogonal frequency division multiplexing (OFDM) symbol in timedomain, and a demodulation reference signal is located in the one OFDMsymbol occupied by the first time-frequency resource unit; and thesecond time-frequency resource unit occupies at least two OFDM symbolsin time domain, and a demodulation reference signal is located in atleast one of the at least two OFDM symbols occupied by the secondtime-frequency resource unit.
 14. The apparatus according to claim 13,wherein: the at least two OFDM symbols occupied by the secondtime-frequency resource unit are adjacent OFDM symbols.
 15. Theapparatus according to claim 14, wherein: in each second time-frequencyresource unit, each of the OFDM symbols occupied by the secondtime-frequency resource unit carries a same quantity of demodulationreference signals.
 16. The apparatus according to claim 14, wherein: ineach second time-frequency resource unit of the control channel, thedemodulation reference signals carried in each of the OFDM symbolsoccupied by the second time-frequency resource unit are located in asame frequency domain location.
 17. The apparatus according to claim 13,wherein: the time-frequency resource of the control channel includes aplurality of first time-frequency resource units or secondtime-frequency resource units.
 18. The apparatus according to claim 13,wherein: the indication information is carried in higher layer signalingor system information.
 19. An apparatus, comprising: one or moreprocessors, and a non-transitory storage medium configure to storeprogram instructions; wherein, when executed by the one or moreprocessors, the instructions cause the apparatus to perform a methodthat comprises: receiving indication information from a base station,wherein the indication information indicates a configuration of atime-frequency resource unit of a control channel, and the configurationis one of at least two configurations of time-frequency resource units;detecting the control channel based on the configuration of thetime-frequency resource unit, wherein: the at least two configurationscomprise a first configuration and a second configuration, the firstconfiguration is corresponding to a first time-frequency resource unitof a control channel, and the second configuration is corresponding to asecond time-frequency resource unit of a control channel; the firsttime-frequency resource unit occupies one orthogonal frequency divisionmultiplexing (OFDM) symbol in time domain, and a demodulation referencesignal is located on the one OFDM symbol occupied by the time-frequencyresource unit; and the second time-frequency resource unit occupies atleast two OFDM symbols in time domain, and a demodulation referencesignal is located on at least one of the at least two OFDM symbolsoccupied by the time-frequency resource unit.
 20. The apparatusaccording to claim 19, wherein: the at least two OFDM symbols occupiedby the second time-frequency resource unit are adjacent OFDM symbols.21. The apparatus according to claim 20, wherein: in each secondtime-frequency resource unit, each of the OFDM symbols occupied by thesecond time-frequency resource unit of the second configuration carriesa same quantity of demodulation reference signals.
 22. The apparatusaccording to claim 20, wherein: in each second time-frequency resourceunit, the demodulation reference signals carried in each of the OFDMsymbols occupied by the second time-frequency resource unit are locatedin a same frequency domain location.
 23. The apparatus according toclaim 19, wherein: the time-frequency resource of the control channelincludes a plurality of first time-frequency resource units or secondtime-frequency resource units.
 24. The method according to claim 19,wherein: the indication information is carried in higher layer signalingor system information.